Sources:
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Much like
Florida, Arizona's population swells in the winter months -- a 2002 study by the Arizona State University reported a boost of nearly 300,000 retirees who temporarily settled in Arizona for the winter. In Lake Havasu City, for instance, the year-round population of 57,000 nearly doubled to 100,000.
Many other retirees have settled in Arizona year-round. The nation's first active adult retirement...